1. Field of the Invention
The present invention relates to a fiber optic distribution cable and, more specifically, to a factory installed termination system where a standard fiber optic cable is outfitted with fiber optic connections along its length at predetermined locations.
2. Description of the Related Art
The use of optical fibers is becoming increasingly popular. This is by virtue of the growth of a variety of applications; including voice communications, audio/video transmissions, data transmissions, and various other internet related services. Typical applications of optical fiber systems include: cable television services, university campus networks, office networks, industrial plant process control systems, and electric utilities. Fiber optics are steadily replacing copper wire as a means of communicating and, thus, optical fiber systems are extended to connect each individual office, room or other location in need of high speed communications.
Due to this increase in demand for fiber optic distribution systems coupled with the need to provide fiber optic access directly to user devices, many individual access points and splices are required. However, providing these numerous individual access points has many drawbacks. Conventionally, in order to provide this access, a main fiber optic cable, containing many optical fibers, must be routed near a multitude of locations. In one embodiment, in order to provide access to a particular location, the fiber optic cable must be spliced at each particular location. Invasively, the external jacket of an optical fiber must be removed to perform splicing. Then the fibers are accessed by cutting open one of the resident buffer tubes wherein the fibers are cut and spliced onto a suitable drop cable. Finally, the exposed area of the cable is closed up and sealed. This process creates a breakout point from which the optical fiber can then be branched to a home. This procedure is typically done in a factory and then brought out to the installation site. In another embodiment, the fiber optic cable enters a splice box where the cable is opened, fibers exposed and spliced onto cables designed specifically to route to a residence, dwelling unit or commercial property. In this case, since the splices are encased by the splice box there is no need for closing up and sealing the cable. The drawback of this method is it requires special equipment and specially trained technicians to perform the task which can be quite costly.
These conventional techniques create an invasive risk as well as associated costs. Optical fibers are extremely fragile and must be handled carefully to avoid breakage. Knots, kinks, twists and bends in the optical fiber will ruin the fiber's ability to transmit light. In some cases, a bend or break in an optical fiber will completely disrupt a system's performance.
Additionally, there is a high cost associated with optical fiber splicing. The actual cost of the fiber is nominal in comparison to the cost of splicing the fiber. Splicing typically requires a skilled technician and special equipment. Typically, field splicing is done by a different set of technicians than those installing the cable. Thus, a special trip to each location is required to setup and splice the fibers. As the number of splices done in a fiber to the premises type application is rather small, the cost per splice may be high given the labor cost and the time required to splice the fiber.
To address these issues, several approaches have been taken to reduce the need for in-the-field splicing. In one approach, disclosed in U.S. Published Patent Application 2005/0175308, a factory prepared fiber optic distribution cable that reduces the need for field splicing has been developed. The prepared cable has a tubular body for protecting a plurality of individual optical fibers. Additionally, the cable has at least one pre-terminated optical fiber withdrawn from the tubular body at a predetermined access location with a connector attached to the pre-terminated optical fiber. The cable also includes a protective shell for protecting the pre-connectorized optical fibers after being removed from the tubular body. In the field, a drop cable is then connected to the pre-connectorized optical fiber near the point of withdrawal from the tubular body. A disadvantage of this system is that excess hardware and connectors are required to bring the optical network to a terminal device. Furthermore, a protective shell, in additional to the tubular body adds additional components to this cable system. For example, the tubular body of the distribution cable includes a protective shell on its exterior for housing the disassociated optical fiber. Additionally, a connector is required to connect this disassociated optical fiber to a drop cable for routing to the terminal device.
Another drawback of this approach is increased installation cost. The inclusion of a tubular body and protective shell effectively increases the minimum working bending radius. Thus, installation becomes more difficult as working product exhibits reduced flexibility. Additionally, where specific installations induce bends in the cable when installed, the rate of fiber damage during installation may increase.
Accordingly, there is a need for a factory assembled, preterminated fiber optic distribution cable that eliminates the need for excess splicing as well as the protective hardware on the exterior of the distribution cable. As such, it is desirable to have a pre-connectorized distribution cable having breakout points at predetermined locations without excess hardware or connectivity means without increasing the minimum working bending radius.